Suction sweeper



June 25; 1929. u s 1,718,302

SUCTION SWEEPER Filed 26, 1924 2 Shee tS-Sheet l Inverfior Marvin E. Nulsen.

June 25, 1929. E, NUL EN 1,718,302

SUCT ION SWEEPER Filed Aug. 26,'l924 .2 Sheets-Sheet 2 Enven+or Marvin E. Nulsen.

BZ/ 16%.WAM AHor'ney Patented June 25, 1929.

.UNITED; STATES PATENT OFFICE.

MARVIN E. NULSEN, OF CANTON, OHIO, ASSIGiNOR TO THE HOOVER COMPANY, OF

NORTH CANTON, OHIO, A CORPORATION 01 OHIO.

SUCTION SWEEPER.

Application filed August 26, 1924. Serial No. 734,839.

This invention relates to that type of suction cleaner wherein there is provided a motor-driven brush which rotates at relatively high speed and beats and sweeps the 6 floor covering being cleaned. The invention is thus applicable to that type of machlne wherein the lips defining the nozzle inlet are maintained at a distance from the surface of the covering being cleaned which 1 covering is raised from the floor against said nozzle lip by the suction produced 1n the cleaner.

In revious brush constructions for cleaners 0 this type serious difficulties have been encountered in that it has heretofore been exceedingly diflicult to jdevelop a brush which is satisfactory when considered from all angles. Certain types of brush w1ll not be found satisfactory as regards end thrust, others do not give a substantially uniform loading of the motor and still other types do not give uniform action throughout the.

length of the nozzle mouth.

. The ob 'ect of this invention is to provide a brush for suction sweepers by the use of which substantially uniform brush drive load is imposed on the motor, end thrust on the brush is eliminated and the action is substantiall uniform throughout the length of the brush.

Other objects and advantages of the nvention will become apparent as the description proceeds, when considered in connection with the drawings in which like numerals indicate like parts throughout, and in which Fig. 1 is an illustration of a suction sweeper showing the application of the invention, parts being broken away for the sake of clearness of illustration;

brush construction;

Fig. 2 is a plan view ofthe specificso-called brush guard fingers 12 which when w the machine is in operationprevents the floor covering from being drawn excessively into the suction nozzle.

In the operation of such a cleaner and when the current is turned on, the motor rotates, and consequently the fan which is provided in the fan chamber also rotates and causes a suction to be created in the suction chamber and the inlet nozzle, and as a result thereof the normal external air pressure causes the floor covering to be drawn u against the guard fingers 12. The brus being connected. with the motor shaft by means of a belt drive, the brush will rotate and will beat as it sweeps that portion of the carpet drawn up against the, nozzle as above explained.

In the structure illustrated, the brush bod 13 is rotatably mounted on .the sha t mounted in the end walls of the nozzle member. On this brush body there is provided a series of individual and separated brush tufts 16 arranged in a predetermined position.

In the structure shown in Fig.2 and diagrammatically shown in Figs. 3 and 4, the brush tufts are arranged substantially in two rows or lines extending contmuously throughout the length of the 'brush and each row or line extending substantially through 180 circumferentially of the brush body. This is the illustration of the broad idea which consists essentially in the proposition of a beating brush wherein the beating and brushing action is substantially uniform throughout the entire length of the brush body. It will be seen that the brush tufts are arranged on the brush body in the form of the two separate helices starting from either end of the brush body and extending to the other end thereof, e'ach through about 180 circumferentially, each in a direction opposite from the other and meeting at the other extremity of the brush body, and it will further be seen that, in order that every portion of the floor covering from end to end of the brush body will be swept and beaten, the brush tufts in the two helical rows are staggered with relation to each other, and it follows from this construction that in each revolution of the brush body-that in any plane perpendicular to the axis of the brush body'the carpet will be swept but once in each revolution of the brush body.

From the above description it will be seen that in the rotation of the brush body there will always be one and only one brush tuft in contact with the floor covering, and this being the case, it follows that the brush drive load on the motor will remain always substantially uniform without serious fluctuation.

' In order that the importance of this invention may be fully understood, attention is directed to the construction previously used and illustrated inPatent No. 1,332,897 issued to Howard Earl Hoover on March 9, 1920, and in connection with which the partic'ular action thereof will be pointed out.

Consider the first bristle tuft shown at the extreme right-hand end of thebrush as disclosed in this patent. It will be noted that as it contacts with the carpet partly drawn up against the nozzle mouth that its stiffness is depended upon to (1) push a portionof the carpet down against the suction and carpet bending forces, (2) and to accelerate the mass of a portion of the carpet from zero velocity to an appreciable downward veloc-- Observation shows that this one tuft is not sufficiently stilf, that is, if it has been so desi ned as not to be too stifi to give a proper brus ing action, to exert the full force represented by the sum of (1) and (2) above with the result that (A) the tuft bends considerably, (B) the carpets downward movement is very slight. I As the next tuft contacts-the carpet it finds the carpet in a slightly lower position (as per B) t an did the first tuft. The rewhat less than the first (D) the carpets downward movement started by the first tuft is added to by] the second tuft.

In this way as t e successive tufts contact the carpet, the carpets downward movement is advanced (there is of course a corresponding sideward movement of the accumulating depression). This downward movement grows and reaches a maximum when the carpetmomentum and bristle stiffness forces (downward) are balanced by the suction and car et bending forces (upward).

, bservation shows that this maximum or balanced condition of carpet downward movement is reached after about one-third of the tufts in the helix have-contacted the carpet. This maximum depression in the carpet; impelled by the remaining tufts in the helix then continues to travel across the nozzle to the extreme left .end and then on beyond the nozzle like an ordinary wave.

From an inspection'of the invention as disclosed in this a plication, it will be seen that I have taken t e point of maximum depression at the left-hand end of'the brush roll and have made it the beginning of a second wave moving back, to the right; The tufts at the beginning ofthe second or reverse helix thus do not have to create a depression as in the first two tufts of the original helix,

for the maximum depression is already there. The tufts of the reverse helix have merely to function as did the tuftsof the last two-thirds of the helix as described with re lation to the above mentioned patent.

It will'be seen that in the construction as it is shown in this disclosure the two helical rows of tufts begin with the same tuft, one

helix advancing (plus) 180 in the length of the brush and the other helix advancing (minus) 180 in the same length. The tufts in the two helices are preferably staggered with reference to one another in order to secure continuous action along the length of the brush roll as previously described, nevertheless the individual tufts contributing to form a particular row or line should be sufficiently close together so that their extremities form in effect a ,well defined helically disposed line of contact with the surface to be acted upon.

By this construction, considering starting at one end of the brush roll when the tufts contact, because of the short contact interval between the bunched tufts at the end, the carpet will almost instantly attain the maximum depression which maximum is carried on to the other end of the brush and then back again ad infinitum for so long as the brush rotates, and when the advanced end of each helix contacts with the carpet a new depression need not be startedfbeginning at zero as described in the construction shown in the Hoover patent above referred sult is that (C) the second tuft bends somet In this construction as previously disclosed and described substantially continuous brush loading of the motor is obtained and uniform brushin action throughout the entire widthof the rush as well as minimum carpet contacts per revolution in any particular plane at right anglesto the brush ody action. But there is one desired feature which it is not possible to obtain in the above construction, but which may be obtained by incorporating the broad idea above described into a slightly different form of bristle tuft arrangement and by suchconstruction it is possible to obtain not only the advantages described with relation to the broad idea but the further advantage of dispensing with end thrust of the brush.

In this specific form of application of my invention the general arrangement is exactly similar to that disclosed with relation to the brush toward the center thereof and on.

reaching the center, the end of the particular helix which is causing the wave will be picked up by the returning helix on the same end of the brush which will return it to the respective end from which it started, at which point the wave will again be started towards the center of the brush roll and ad infinitum.

Having fully disclosed and described my invention with such degree of particularity which would enable one skilled in the art relating thereto to use and employ said invention,

I claim 1. In a suction sweeper the combination of a revoluble body, and agitating elements arranged to form helically disposed lines of contact for engagement with a surface to be acted upon and extending circumferentially around said body, said helically disposed lines of contact meeting at common terminals.

2. In a suction sweeper, a revoluble body, tufts arranged thereon in paired rows extending helically from end to end of the body, the rows of the pair starting at a common point, wrapping in opposite directions and terminating in a common point.

3. In a suction sweeper, a revoluble brush body, rows of bristle tufts on the brush body, the rows being paired on the body in the form of oppositely wound helices having common terminals.

4. In a suction sweeper, a rotatable member, agitating means arranged thereon in paired rows, the rows extending helically and having a common starting point, wrapping in opposite directions and terminating in a common point.-

5. In a suction sweeper, a revoluble member, agitator means arranged thereon in rows, there being more than one row thereof, each row of the agitator means separated throughout the major portion of its length from every other row on the body, but having an end thereof in common with an end of another row.

Signed at North Canton in the county of Stark and State of Ohio this 15th day of August, A. D. 1924.

MARVIN E. NULSEN. 

